DS1501WN

Real Time Clock Overview

The DS1501WN is a Y2K-compliant real-time clock/calendar integrated circuit manufactured by Analog Devices Inc./Maxim Integrated. It features a parallel byte-wide interface, 256 bytes of battery-backed NV SRAM, and operates at +3.3V with an industrial temperature range of -40°C to +85°C. The device includes programmable watchdog timers, RTC alarms, power-on reset, and battery monitors. Timekeeping registers store century, year, month, date, day, hours, minutes, and seconds in 24-hour BCD format with automatic leap-year compensation valid until 2100.

Real Time Clock Feature Summary

• Y2K-Compliant RTC with Automatic Leap-Year Compensation Valid Up to Year 2100
• 256 Bytes Battery-Backed NV SRAM with Auxiliary Battery Input (VBAUX)
• Programmable Watchdog Timer and Day-of-Week/Date Alarm
• +3.3V Operation with Industrial Temperature Range (-40°C to +85°C)

Real Time Clock Applications

• Remote Systems
• Battery-Backed Systems
• Telecom Switches

Real Time Clock Procurement Notes

Verify the specific package type for the 'WN' suffix against official documentation, as standard listings typically specify WE or WEN TSOP packages. Confirm availability status directly with the manufacturer or authorized distributors, as lead times and stock levels fluctuate. Ensure compliance with RoHS standards indicated by the '+' designation if applicable to the specific revision.

Real Time Clock Selection Notes

Select the DS1501WN for applications requiring a standalone RTC with parallel interface and +3.3V logic compatibility. Ensure the design accommodates the 28-pin TSOP package dimensions. Verify crystal selection matches the 6pF or 12.5pF load capacitance settings via the CS bit. Confirm that the system power supply remains within the 3.0V to 3.6V operating range for optimal performance.

Real Time Clock Part Context

The DS1501 series comprises full-function RTCs with watchdog timers and NV SRAM. The DS1501 variant is a chip-only solution, distinct from the DS1511 which integrates an embedded battery and crystal in a DIP module. Both share identical register maps and functionality, differing primarily in physical packaging and internal power source integration.

Real Time Clock Replacement Considerations

The DS1511W+ serves as a functional equivalent with identical electrical characteristics but differs in packaging (EDIP vs TSOP) and contains an embedded battery. Cross-referencing pinouts and voltage specifications is required when substituting.